Wet Chemical Treatment and Mg Doping of p-InP Surfaces for Ohmic Low-Resistive Metal Contacts

Manufacturing a low-resistive Ohmic metal contact on p-type InP crystals for various applications is a challenge because of the Fermi-level pinning via surface defects and the diffusion of p-type doping atoms in InP. Development of wet-chemistry treatments and nanoscale control of p-doping for InP surfaces is crucial for decreasing the device resistivity losses and durability problems. Herein, a proper combination of HCl-based solution immersion, which directly provides an unusual wet chemical-induced InP(100)c(2 × 2) atomic structure, and low-temperature Mg-surface doping of the cleaned InP before Ni-film deposition is demonstrated to decrease the contact resistivity of Ni/p-InP by the factor of 10 approximately as compared to the lowest reference value without Mg. Deposition of the Mg intermediate layer on p-InP and postheating of Mg/p-InP at 350 °C, both performed in ultrahigh-vacuum (UHV) chamber, lead to intermixing of Mg and InP elements according to X-ray photoelectron spectroscopy. Introducing a small oxygen gas background (O₂ ≈ 10⁻⁶ mbar) in UHV chamber during the postheating of Mg/p-InP enhances the indium outdiffusion and provides the lowest contact resistivity. Quantum mechanical simulations indicate that the presence of InP native oxide or/and metal indium alloy at the interface increases In diffusion.     

Toxicological screening with formula-based metabolite identification by liquid chromatography/time-of-flight mass spectrometry

An analytical procedure was evaluated for the comprehensive toxicological screening of drugs, metabolites, and pesticides in 1-mL urine samples by TurboIon spray liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS) in the positive ionization mode and continuous mass measurement. The substance database consisted of exact monoisotopic masses for 637 compounds, of which an LC retention time was available for 392. A macroprogram was refined for extracting the data into a legible report, utilizing metabolic patterns and preset identification criteria. These criteria included +/-30 ppm mass tolerance, a +/-0.2-min window for absolute retention time, if available, and a minimum area count of 500. The limit of detection, determined for 90 compounds, was <0.1 mg/L for 73% of the compounds studied and >1.0 mg/L for 6% of the compounds. For method comparisons, 50 successive autopsy urine samples were analyzed by this method, and the results confirmed by gas chromatography/mass spectrometry (GC/MS). Findings for parent drugs were consistent with both methods; in addition, LC/TOFMS regularly revealed apparently correct findings for metabolites not shown by GC/MS. Mean and median mass accuracy by LC/TOFMS was 7.6 and 5.4 ppm, respectively. The procedure proved well-suited for tentative identification without reference substances. The few false positives emphasized the fact that all three parameters, exact mass, retention time, and metabolite pattern, are required for unequivocal identification.     

Etiology of pneumonia and other common childhood infections requiring hospitalization and parenteral antimicrobial therapy. SE-TU Study Group

The etiology of acute lower respiratory tract infections (mostly pneumonia) in children is well characterized, but these are only some of the community-acquired infections warranting parenteral antimicrobial therapy. We prospectively evaluated all such infections among children aged 3 months to 15 years by use of blood cultures, examination of nasopharyngeal aspirates, and serologies for 15 viral, 7 bacterial, and 1 protozoal agent. Immunocompromised patients and those with urinary tract infection, meningitis, or osteoarticular infection were excluded. In all, 170 children were included. The pathogenic agent was identified in 62% of the cases. Bacteria were detected in 54%, and a pneumococcus was found in 59% of the cases identified. Viruses were found in 15% overall. Sole bacterial or viral infections were detected in 47.1% and 8.1%, respectively. Since thorough screening established the etiology in less than two-thirds of patients ill enough to be hospitalized and treated parenterally, better diagnostics are needed, especially to identify those who would truly benefit from antimicrobial therapy.     

Precision of dual energy x-ray absorptiometry in the upper extremities

Dual energy x-ray absorptiometry (DEXA) has been shown to be a precise method for measuring bone mineral density (BMD) and content (BMC) in lumbar spine and proximal femur, but it has not been widely used in other skeletal sites. The in vivo day-to-day precision of DEXA (Norland XR-26) for seven anatomic sites in the upper extremities was evaluated by twice measuring both the right and left sides in ten subjects. For consistently defined regions-of-interest, the following precision values (coefficient of variation) were obtained for BMD and BMC: 0.8% and 1.0% (proximal humerus); 0.5% and 0.5% (humeral shaft); 0.7% and 0.5% (radial shaft); 1.3% and 1.1% (ulnar shaft); 0.7% and 1.0% (distal radius); 0.7% and 1.2% (distal ulna); 0.4% and 0.6% (hand). The initially observed relative side-to-side differences did not change significantly in the repeated measurements. Our results indicate that DEXA is a precise method for assessment of BMD and BMC also in the upper extremities.     

Risk-benefit evaluation of nuclear power plant siting

An assessment scheme is described for the risk-benefit analyses of nuclear power versus conventional alternatives. Given the siting parameters for the proposed nuclear plant an economic comparison is made with the most advantageous competitive conventional production scenario. The economic benefit is determined from the differential discounted annual energy procurement cost as a function of the real interest rate and amortization time. The risk analysis encompasses following factors: radiation risks in normal operation, reactor accident hazards and economic risks, atmospheric pollutants from the conventional power plants and fuel transportation. The hazards are first considered in terms of probabilistic dose distributions. In the second stage risk components are converted to a compatible form where excess mortality is used as the risk indicator. Practical calculations are performed for the power production alternatives of Helsinki where district heat would be extracted from the nuclear power plant. At the real interest rate of 10% and amortization time of 20 yr the 1000 MW(e) nuclear option is found to be $9.1 m per yr more economic than the optimal conventional scenario. Simultaneously the nuclear alternative is estimated to reduce excess mortality by 2–5 fatal injuries annually.     

Determination of chromium in human milk, serum and urine by electrothermal atomic absorption spectrometry without preliminary ashing

In the present study a Perkin-Elmer 5000 atomic absorption spectrometer equipped with a tungsten--iodide lamp for improved background correction at the 357.9 nm chromium absorption line and an HGA 500 graphite furnace were employed for the direct determination of chromium in human serum, milk and urine. The method of standard additions was used: 0.25-0.75 ng Cr was added to 1 ml samples. Except for urine samples, a dilution of 1 + 1 to 1 + 2 with H2O was necessary in order to obtain correct calibration curves. The average concentration of chromium in all the samples of normal subjects was less than 0.5 ng Cr ml-1. The day-to-day variation for all of the pooled samples was around 10% (relative standard deviation). For urine, the accuracy of the method was tested by comparing the results of another laboratory for the same two round robin samples. Excellent agreement was found between the present method and those of the other laboratory that had used isotope dilution--mass spectrometry and continuum source wavelength modulated echelle--atomic absorption spectrometry to define the chromium concentration in the samples. The detection limit of the method, 0.05 ng Cr ml-1 for urine and serum and 0.1 ng Cr ml-1 for human milk, was sufficient for the biological fluids analyzed. The method was employed for the determination of chromium in 24-h urine samples of maturity onset diabetics supplemented with 20 or 200 micrograms Cr3+ d-1 for six weeks. It was shown that the 24-h urinary chromium excretion accurately indicates the daily dietary chromium intake of these patients.     

Correction to: Digitalization in knowledge work: the dream of enhanced performance

According to decision by the rector of University of Tampere, a version of the paper was submitted and published due to negligence.     

Investment project as an internal corporate venture

A capital investment project exhibits both deliberate and emergent strategic elements. The emergent strategic elements have been conceptualized as a project strategy, which is formed in a project to attain business-oriented results and to cope with organizational and market environments. We use corporate venturing literature to explain the formation of the strategy of an individual project. In the project studies that consider the deliberate strategic elements with projects, a project has been explained to solely implement the strategy of its parent organization: This paper addresses the relationship between a project and its parent and explains how the dimensions of the parent-project relationship affect the formation of a project's strategy which may diverge from the intended strategy of the parent. The empirical study is a case study on four investments projects in Neste Oil, a firm operating in the oil refining industry. The projects have a degree of autonomy in relation to the parent, depending on their relatedness to the existing capabilities of the parent.     

Epidermal growth factor modulates tyrosine phosphorylation of p130Cas. Involvement of phosphatidylinositol 3'-kinase and actin cytoskeleton

Epidermal growth factor (EGF) treatment of Rat-1 cells expressing human EGF receptor results in the modification of the tyrosine phosphorylation of the p130 Crk-associated substrate (Cas), a novel signaling molecule residing in focal adhesions. At low, mitogenic concentrations (<10 ng/ml), EGF treatment induced a rapid and transient tyrosine phosphorylation of Cas and promoted the formation of a Cas-adapter protein Crk complex in intact cells. The increase in tyrosine phosphorylation of Cas paralleled an increase in the cellular content of actin stress fibers and occurred via a pathway that depended on the integrity of the cytoskeleton. Further, phosphatidylinositol 3'-kinase activity was found to be required for the EGF-stimulated Cas phosphorylation and actin polymerization. At high concentrations (>30 ng/ml), EGF treatment resulted in the tyrosine dephosphorylation of Cas in a time-dependent manner with a concomitant decrease in the length and number of actin stress fibers. Thus, Cas exhibits an unusual bell-shaped dose-response curve in response to EGF stimulation. These results demonstrate a novel signaling role for EGF in inducing changes in tyrosine phosphorylation of Cas and Cas-Crk complex formation and suggest that Cas could be a signaling component in EGF-mediated signal transduction.     

Evaluation of glaucoma patients referred to a university clinic during one year

Infections by Aeromonas spp. are a rare cause of systemic infection in normal and immunocompromised hosts. We report the cases of two patients with acute non-lymphoblastic leukemia who developed septic shock by Aeromonas species with unusual soft-tissue complications. One patient who was undergoing consolidation chemotherapy developed septic shock by Aeromonas hydrophila with rhabdomyolysis and subsequent soft-tissue destruction consistent with myonecrosis. She recovered with combination antibiotic therapy and supportive care. The second patient developed neutropenia due to ganciclovir treatment for post-allogeneic transplant cytomegalovirus antigenemia. He developed a rapidly progressive septic shock due to Aeromonas sobria with rhabdomyolysis, multi-organ failure and bilateral lower limb myonecrosis, and died within 48 hours. The portal of entry was not identified in either case. These cases confirm the potentially aggressive nature of these bacteria in neutropenic cancer patients with an unusual tendency to produce muscular and soft-tissue destruction.